Field of The Invention
The present invention relates to polyaniline derivatives which can be dissolved in organic solvents and with which they are possible to produce a film having flexibility, and to a process for preparing the same.
In recent years, the application of polyaniline as a new electronic or conductive material in such varied fields as, for example, cell electrode materials, antistatic materials, electromagnetic shielding materials, functional devies--e.g., photoelectric transducers, optical memories and various sensors-, display devices, various hybrid materials, transparent electroconductors, and various terminal equipment.
However, generally, polyanilines have a highly developed .pi.-conjugated systems, and therefore the main chain of polyaniline is stiff, and the interactions between the chains of molecules are strong. Because of the many strong hydrogen bonds which exist between the molecule chains, there are many organic solvents in which polyaniline is insoluble, nor can the polyaniline, and cannot be melted by heating. Therefore, a serious defect arises from the inability of polyanilie to be processed to a film.
Therefore, composite materials were prepared by impregnating a monomer comprising aniline with a backing of a desired shape such as that of a porous material or a fiber made of a polymer. The monomer was then polymerized by contacting the monomer with polymerizing catalysts or by electrolytic oxidation, or by using a thermal plasticity polymer powder. In contrast, a polyaniline soluble only in N-methyl-2-pyrrolidone in synthesized by controlling the reaction temperature and selecting polymerizing catalysts (M. Abe et al.; J. Chem. Soc, Chem. Commun., 1989,1736). However, this polyaniline also is insoluble in other ordinary organic solvents, and therefore the range of application of the polyaniline was limited. In addition, although soluble polyaniline derivatives were synthesized from many kinds of aniline derivatives, the films made of such polyaniline derivatives did not exhibit sufficient flexibility.